Qualitative Risk Assessment of the Acquisition of Meticillin‐Resistant Staphylococcus aureus in Pet Dogs

This article presents a qualitative risk assessment of the acquisition of meticillin‐resistant Staphylococcus aureus (MRSA) in pet dogs, representing an important first step in the exploration of risk of bidirectional MRSA transfer between dogs and humans. A conceptual model of the seven potential pathways for MRSA acquisition in a dog in any given 24‐hour period was developed and the data available to populate that model were considered qualitatively. Humans were found to represent the most important source of MRSA for dogs in both community and veterinary hospital settings. The environment was found to be secondary to humans in terms of importance and other dogs less still. This study highlights some important methodological limitations of a technique that is heavily relied upon for qualitative risk assessments and applies a novel process, the use of relative risk ranking, to enable the generation of a defensible output using a matrix combination approach. Given the limitations of the prescribed methods as applied to the problem under consideration, further validation, or repudiation, of the findings contained herein is called for using a subsequent quantitative assessment.     

Pseudo-likelihood inference for clustered binary data

The maximum likelihood procedure to estimate paraneters of a model has scveral attractive properties including the existence of the covariance matrix which yield asymptotic covariances: for a sample size N the asymptotics are in general of order 1/N. Here we give an asymptotic for the skewness of the distribution of the maximum likelihood estimator of a parameter; this is of order 1/ n2 and this expression is new. Applications relate to the parameters of (i) the Poisson, binomial, and normal density. (ii) the gamna density and (iii) the Beta debsity. Other application are being considered. The expression for the asymptotic skowness at one phase of the study tured out to be unusually complicated involving the asymptotic expressions for variance and bias. When these were identified a much simpler compact expression appeared which we now describe. The work is a much improved treatment of the subject described in Shenton and Bowman (Mariunm likelihood estimation in small samples, Griffin. 1977).     

Licensure as a Dilemma for Social Work Education: Findings of a National Study

Abstract

This paper reports on the first national survey to study the perceptions of MSW social work faculty of the relationship between licensing examinations and social work education. A non-random sample of 242 faculty from 39 systematically selected accredited schools from all states with licensure responded. The questionnaire focused on the impact of the national licensure examination on teaching, curriculum, and students. Among the major findings was that students are perceived as regarding the licensure exam as important to the profession and significant to their future. Faculty, however, only take the examination into consideration in the advisement process. Generally, they are unfamiliar with the examination's content, and they disregard it in curriculum development and in teaching.     

Discrete‐time survival trees

Tree‐based methods are frequently used in studies with censored survival time. Their structure and ease of interpretability make them useful to identify prognostic factors and to predict conditional survival probabilities given an individual's covariates. The existing methods are tailor‐made to deal with a survival time variable that is measured continuously. However, survival variables measured on a discrete scale are often encountered in practice. The authors propose a new tree construction method specifically adapted to such discrete‐time survival variables. The splitting procedure can be seen as an extension, to the case of right‐censored data, of the entropy criterion for a categorical outcome. The selection of the final tree is made through a pruning algorithm combined with a bootstrap correction. The authors also present a simple way of potentially improving the predictive performance of a single tree through bagging. A simulation study shows that single trees and bagged‐trees perform well compared to a parametric model. A real data example investigating the usefulness of personality dimensions in predicting early onset of cigarette smoking is presented. The Canadian Journal of Statistics 37: 17‐32; 2009 © 2009 Statistical Society of Canada     

‘Between authenticity and pretension’: parents', pupils' and young professionals' negotiations of minority ethnic middle‐class identity

Despite an increasing sociological interest in the middle classes and their educational practices, research has largely concentrated on the white middle classes. This paper considers the case of the minority ethnic (ME) middle classes through empirical data from a small, exploratory study conducted in England with 36 minority ethnic, ‘middle‐class’ individuals (parents, pupils and young professionals) from a range of ME backgrounds. It is argued that participants experienced ME middle‐class identity as a profoundly conflictual and precarious space, negotiated through a matrix of relational classed and racialized positionings. ‘Authentic’ middle‐classness remains the preserve of white society due to racial inequalities and the dominance of whiteness as the popularly legitimated marker of middle classness. Moreover, attempts to define an acceptable, legitimate and principled ME middle‐class identity are compromised by the discursive threats of ‘inauthenticity’, ‘pretension’ and ‘misrecognition’.     

An equation to predict maximum acceptable loads for repetitive tasks based on duty cycle: evaluation with lifting and lowering tasks

Recently, an equation was developed to predict maximal acceptable effort (MAE) for repetitive tasks based on the product of task frequency and effort duration (ie. duty cycle). This equation has been shown to closely match data from psychophysical studies of the upper extremities. In the current paper, the applicability of this equation was tested on lifting and lowering data from Snook and Ciriello (1991) and was found to fit closely, even at very low duty cycles.